1. Field of the Invention
Embodiments of the present invention relate to an anisotropic conductive film composition. More particularly, embodiments of the present invention relate to an anisotropic conductive film composition including a styrene-acrylonitrile copolymer and exhibiting improved adhesion and low contact resistance characteristics.
2. Description of the Related Art
In general, an anisotropic conductive film (ACF) refers to a film-type adhesive having conductive particles dispersed in an insulating adhesive binder. As such, the ACF may provide connections between electrical components, e.g., semiconductor elements, circuits, and so forth. More specifically, the ACF may be compressed between electrical components, so the conductive particles may establish an electrical connection therebetween, and the insulting adhesive binder may flow away from the electrical components to provide an insulating coating around the resultant electrical connection. The binder may also provide mechanical bonding between the electrical components. Accordingly, the ACF may be used for electrical connection in, e.g., liquid crystal displays (LCDs), tape carrier packages (TCPs), printed circuit boards (PCBs), and so forth.
Conventional ACFs may include a binder, e.g., an epoxy-based binder or a (meth)acrylate-based binder, mixed with a curing agent. However, the conventional epoxy-based and/or (meth)acrylate-based binder may exhibit insufficient adhesive properties and a relatively low glass transition temperature, thereby imparting poor mechanical connection and adhesion reliability to the conventional ACF.
In addition to insufficient adhesive properties, the epoxy-based binder may require high curing temperature and long curing time, thereby imparting low long-term reliability to the ACF. With respect to the (meth)acrylate-based binder, in addition to insufficient adhesive properties, the (meth)acrylate-based binder may exhibit low heat and moisture resistance. Additionally, the (meth)acrylate-based binder may have different flow properties with respect to the curing agent due to different rheology characteristic thereof, thereby causing either excessive generation of foam upon low curing rate or low conductivity upon high curing rate, which in turn, may result in either low reliability or low conductivity, respectively.